Reach of Substation Glitch Baffles Officials
By Peter Whoriskey and Steven Mufson
Washington Post Staff Writers
Wednesday, February 27, 2008
MIAMI, Feb. 26 -- Commuter trains stopped on their elevated tracks, elevators halted between floors, traffic lights went dark, and two nuclear power reactors were shut down Tuesday afternoon as a cascading power outage left millions of Floridians without electricity, according to state officials.
Power was restored to most customers within four hours, but not before the outage had prompted bouts of panic, particularly as the extent of the problems became known.
The state's largest electric company said the disruption was caused by a small malfunction in a transmission substation west of Miami, where a fire erupted. City and federal officials quickly rejected the possibility of a terrorism or criminal link.
Florida Power and Light officials could not readily explain how the minor glitch could cause extensive outages as far away as Tampa and Daytona Beach. Safeguards built into the electrical system, they said, should have contained the trouble.
"That's the part we don't have an answer for yet," FP&L President Armando Olivera said.
Fire rescue officials received more than 30 calls from Miami-Dade County alone, excluding downtown Miami, regarding people stuck in elevators.
"You can imagine the hysteria," said Lt. Elkin Sierra of Miami-Dade Fire Rescue. "One woman thought she was going into labor."
Others descended stairs for dozens of flights in high-rises served by elevators. Those who had been at work headed home at midafternoon. Several South Florida hospitals were forced to switch to generator power. Shoppers wandered uncertainly through the aisles of dimmed department stores. Parents rushed out to schools to pick up their children.
Out on the streets, an impromptu rush hour made clear the blackout's most pervasive effects: Traffic crawled on city streets because stoplights no longer worked and tentative drivers braked their way through intersection after intersection. Police were assigned to direct traffic and "eliminate or alleviate any possible road rages," a police spokesman said.
The system of commuter trains that carry more than 30,000 people around the Miami area also stopped. That left passengers at least temporarily stuck on the tracks.
Given the extent of the outage on a clear day in Miami, many wondered at first whether it had malicious origins.
"What I can assure people is that this was something technical; it wasn't anything criminal-related," Miami-Dade County Mayor Carlos Alvarez said.
Laura Keehner, a spokeswoman for the Department of Homeland Security in Washington, said there was "no indication of a terror nexus at this time."
Olivera apologized to customers and state officials Tuesday evening. By 5 p.m., he said, 8,000 of the 475,000 households and businesses affected in the FPL system were still without power.
He said that a faulty disconnect switch at a substation in west Miami-Dade County had failed and that a piece of equipment controlling voltage at the substation caught fire.
Small incidents can sometimes lead to widespread power failures because they may create a cascade of secondary problems. When demand for power suddenly exceeds the electrical supply, transmission and distribution systems begin to cut off customers.
Power companies call these automatic shut-offs "shedding the load," and they are meant to prevent further damage to the power grid.
Tuesday's fire led to problems in two major power lines between Miami and Daytona and the shutdown of 20 other substations. "Under normal circumstances, an equipment failure of that kind would not cause the extended outage we saw today," Olivera said.
At 1:09 p.m., about a minute after the substation problem, the two nuclear reactors at FPL's Turkey Point Plant detected "a disturbance in the grid" and shut down, as they are designed to do. That took 1,400 megawatts of generating capacity offline. Two coal-fired units at the same complex also shut down.
Olivera said that the company's nuclear units had "shut down as designed."
Within three minutes or so of the substation problem, customers began to lose power. Because other Florida utilities are connected to the same grid, FPL's problems spread throughout the state.
Olivera estimated that, at the peak of the outage, a million households and businesses were affected.
A Progress Energy spokesman, Scott Sutton, said 153,000 of its customers were affected.
The outage was not nearly as extensive or prolonged as the regional blackout on Aug. 14, 2003, the largest in North American history, when tree branches damaging power lines in Ohio ended up causing power loss to 50 million people in eight states and Ontario, Canada.
But the disruption Tuesday was significant enough that the Florida state emergency operations center in Tallahassee was monitoring the situation. Officials said they were ready to provide assistance if the outage persisted after dark and local governments needed help to maintain order.
By sundown, however, order and electricity had been restored to most of the affected areas. Authorities said an investigation could take weeks.
Mufson reported from Washington.
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